In U.S. Pat. No. 8,673,101 (Brandstrom) issued Mar. 18, 2014 is shown a composite reinforcing bar formed by providing a reinforcing material supply of fiber strands, a resin supply bath, and a puller for pulling the resin-impregnated reinforcing material through the resin bath. The material is wound on a holder, while the resin remains unset, rotated about its axis on a drive system so that the material is wrapped around a plurality of guides at spaced positions around the axis such that the fed length of the body is wrapped from one guide to the next to form bent portions of the body wrapped at least partly around each guide with optional straight portions between the bars. Each guide has peripheral grooves at longitudinally stepped positions which are shaped to mold the bent portions to a required bent shape. The holder is indexed along the axis to wrap a length of the bar. The bar is then cured either with the holder in place while the winding action continues or with the holder removed to a curing location when full.
This method can be used to form shaped portions at the ends of straight positions of the rebar where the guides are spaced around a winding axis to leave the straight portions between the guides or can be used to form a helical coil of the rebar where the guide itself is helical and engages and supports the rebar along the full length.
That is the guide or guides can engage the rebar along part of the length of the rebar all along the whole length of the rebar. The guides typically form a channel into which the rebar is placed prior to curing so that a surface of the channel supports the rebar during the curing action.
It is also known that the exterior surface of the rebar should carry in some cases a particulate material partly embedded in the exterior of the rebar so that the particulate material projects outwardly for engagement with the concrete or other material into which the rebar is embedded. This is known to provide an increased frictional engagement between the rebar and the concrete. Typically the particular material is sand but other particulate materials can be used.